I was wondering if some of you more seasoned EMD mechanics could help me understand the adjustment and checking of valve bridges on EMD 567B engines.

I work on two 8-567Bs and one of them has some tapping sounds coming from some of the cylinder heads. The logical place to check first in my mind are the valve bridges. I am familiar with what the EMD maintenance manual says about them, but I would like to hear your opinions on how to check for defective lash adjusters. I understand that as the rocker arms wear, the clearances enlarge and decrease the oil pressure getting to the lash adjusters decreases. But my inexperienced ear says something is defiantly wrong. You can hear a particular loud tapping from 200ft away from the engine when it is idling. And when you are around the engine, it seems to be coming from 1 or 2 cylinder heads.

I know there is a 1/16 thick gauge you use to check the clearance when a particular cylinder is at TDC. If that gauge does not fit, does that mean that the lash adjuster is defective and needs to be replaced?

I should also add that I know for a fact that no maintenance has been done to these engines other than oil changes and fuel filter changes since around 1998. They have been in on-off service ever since.

Help with this would be greatly appreciated. Don't be afraid to start from square 1 if what I've said is all wrong! Thanks,

- Walker

The first thing I would do would be go through the entire engine and set the exhaust valve and injector timing properly. That way you can troubleshoot from a known baseline. Set the timing when the engine is warm.

You would be amazed how out of timing adjustment these engines will run.

EBL